1. Field of the Invention
The present invention relates to a manufacturing method of a liquid discharge head substrate (a substrate for a liquid discharge head), and in particular relates to a manufacturing method of substrate for an ink jet recording head for use in an ink jet recording head that discharges ink onto a recording medium to perform recording.
2. Description of the Related Art
One application example of a liquid discharge head is an ink jet recording head that discharges ink as liquid droplets onto a recording medium (typically, paper) by energy to perform recording. For the ink jet recording head, there is a known technique in which energy generating elements that are mounted on a surface of a substrate are supplied with ink from an opposite surface of the substrate via a supply port passing from the opposite surface through to the surface. A manufacturing method of a substrate for this type of ink jet recording head is disclosed in U.S. Patent Application No. 2007/0212890.
In the manufacturing method described in U.S. Patent Application No. 2007/0212890, an opening is formed in an etching mask layer on an opposite surface of a silicon substrate, a depression is formed in silicon exposed in the opening by dry etching, a laser, or the like, and the silicon substrate is wet etched from the depression to form a supply port that passes through the substrate.
However, in the method described in U.S. Patent Application No. 2007/0212890, the opening is formed in an entire area of the opposite surface of the substrate corresponding to the supply port, which requires patterning to be performed on the etching mask layer. A photolithography process is necessary for this operation.